Impact of anatase and rutile titanium dioxide nanoparticles on uptake carriers and efflux pumps in Caco-2 gut epithelial cells

International audienceTiO2 microparticles are widely used in food products, where they are added as a white food colouring agent. This food additive contains a significant amount of nanoscale particles; still the impact of TiO2 nanoparticles (TiO2-NPs) on gut cells is poorly documented. Our study aimed at evaluating the impact of rutile and anatase TiO2-NPs on the main functions of enterocytes, i.e. nutrient absorption driven by solute-liquid carriers (SLC transporters) and protection against other xenobiotics driven by efflux pumps from the ATP-binding cassette (ABC) family. We show that acute exposure of Caco-2 cells to both anatase (12 nm) and rutile (20 nm) TiO2-NPs induce early upregulation of a battery of efflux pumps and nutrient transporters. In addition they cause overproduction of reactive oxygen species and misbalance redox repair systems, without inducing cell mortality or DNA damage. Taken together, these data suggest that TiO2-NPs may increase the functionality of gut epithelial cells, particularly their property to form a protective barrier against exogenous toxicants and to absorb nutrients

Evaluation of a new method for the collection and measurement of 8-isoprostane in exhaled breath for future application in nanoparticle exposure biomonitoring

International audienceBackground. In the field of nanoparticle exposure biomonitoring, oxidative stress biomarkers measured in exhaled breath condensate appear promising to detect early respiratory effects in workers handling nanomaterials. However, condensation is known for its poor efficiency in collecting non-volatiles in exhaled breath, leading to the low sensitivity of such measurements. Moreover, to be easily used in field studies on large groups of workers, the collection device must be disposable and convenient. Objectives. In this study, we have tested a totally disposable commercial device that allows for the easy dry collection of exhaled air after filtration on a patented filter. The suitability and efficiency of the SensAbues (SB) device for collecting 8-isoprostane were evaluated and compared to the RTube (RT). Methods. Seven healthy volunteers performed two 15 min collections of exhaled breath, one with the SB and one with the RT. Blank devices were used to determine the background levels induced by each device. 8-isoprostane was measured in all samples using an EIA technique. Results. The levels of 8-isoprostane in the exhaled breath of volunteers after collection with the SB were significantly higher than those after collection with the RT. Moreover, the levels obtained in volunteers with the SB were significantly higher than background levels obtained in blank devices, which was not the case for the RT. Conclusions. This is the first study to report the ability of the SB device to collect and measure 8-isoprostane in exhaled breath. The proposed method offers better sensitivity than a classical collection with the RT device and should be further explored before future application in biomonitoring studies. List of abbreviations EBC exhaled breath condensate EIA(s) enzyme immunoassay(s) NP(s) nanoparticle(s) RT RTube SB SensAbue

Toxicokinetic considerations in using a suite of markers to better understand occupational health risk from PAH exposure

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Evaluation of DNA Adducts, DNA and RNA Oxidative Lesions, and 3-Hydroxybenzo( a )pyrene as Biomarkers of DNA Damage in Lung Following Intravenous Injection of the Parent Compound in Rats

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Modeling of the Internal Kinetics of Benzo(a)pyrene and 3-Hydroxybenzo(a)pyrene Biomarker from Rat Data

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Modeling of the internal kinetics of benzo(a)pyrene and 3-hydroxybenzo(a)pyrene biomarker from rat data

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Is exhaled breath condensate representative of deep lung and suitable for exposure assessment to nanoparticles?

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Is exhaled breath condensate representative of deep lung and suitable for exposure assessment to nanoparticles?

International audiencePas de résum